The rx-vlan-filter feature flag prevents unexpected tagged frames on
the wire from reaching the kernel in promiscuous mode.
Disable this offloading feature in the lan7800 controller whenever
IFF_PROMISC is set and make sure that the hardware features
are updated when IFF_PROMISC changes.
Signed-off-by: Markus Blöchl <markus.bloe...@ipetronik.com>
---
Notes:
When sniffing ethernet using a LAN7800 ethernet controller, vlan-tagged
frames are silently dropped by the controller due to the
RFE_CTL_VLAN_FILTER flag being set by default since commit
4a27327b156e("net: lan78xx: Add support for VLAN filtering.").
In order to receive those tagged frames it is necessary to manually disable
rx vlan filtering using ethtool ( `ethtool -K ethX rx-vlan-filter off` or
corresponding ioctls ). Setting all bits in the vlan filter table to 1 is
an even worse approach, imho.
As a user I would probably expect that setting IFF_PROMISC should be enough
in all cases to receive all valid traffic.
Therefore I think this behaviour is a bug in the driver, since other
drivers (notably ixgbe) automatically disable rx-vlan-filter when
IFF_PROMISC is set. Please correct me if I am wrong here.
drivers/net/usb/lan78xx.c | 33 +++++++++++++++++++++++++--------
1 file changed, 25 insertions(+), 8 deletions(-)
diff --git a/drivers/net/usb/lan78xx.c b/drivers/net/usb/lan78xx.c
index 65b315bc60ab..ac6c0beeac21 100644
--- a/drivers/net/usb/lan78xx.c
+++ b/drivers/net/usb/lan78xx.c
@@ -2324,13 +2324,15 @@ static int lan78xx_set_mac_addr(struct net_device
*netdev, void *p)
}
/* Enable or disable Rx checksum offload engine */
-static int lan78xx_set_features(struct net_device *netdev,
- netdev_features_t features)
+static void lan78xx_update_features(struct net_device *netdev,
+ netdev_features_t features)
{
struct lan78xx_net *dev = netdev_priv(netdev);
struct lan78xx_priv *pdata = (struct lan78xx_priv *)(dev->data[0]);
unsigned long flags;
- int ret;
+
+ if (netdev->flags & IFF_PROMISC)
+ features &= ~NETIF_F_HW_VLAN_CTAG_FILTER;
spin_lock_irqsave(&pdata->rfe_ctl_lock, flags);
@@ -2353,12 +2355,30 @@ static int lan78xx_set_features(struct net_device
*netdev,
pdata->rfe_ctl &= ~RFE_CTL_VLAN_FILTER_;
spin_unlock_irqrestore(&pdata->rfe_ctl_lock, flags);
+}
+
+static int lan78xx_set_features(struct net_device *netdev,
+ netdev_features_t features)
+{
+ struct lan78xx_net *dev = netdev_priv(netdev);
+ struct lan78xx_priv *pdata = (struct lan78xx_priv *)(dev->data[0]);
+ int ret;
+
+ lan78xx_update_features(netdev, features);
ret = lan78xx_write_reg(dev, RFE_CTL, pdata->rfe_ctl);
return 0;
}
+static void lan78xx_set_rx_mode(struct net_device *netdev)
+{
+ /* Enable or disable checksum offload engines */
+ lan78xx_update_features(netdev, netdev->features);
+
+ lan78xx_set_multicast(netdev);
+}
+
static void lan78xx_deferred_vlan_write(struct work_struct *param)
{
struct lan78xx_priv *pdata =
@@ -2528,10 +2548,7 @@ static int lan78xx_reset(struct lan78xx_net *dev)
pdata->rfe_ctl |= RFE_CTL_BCAST_EN_ | RFE_CTL_DA_PERFECT_;
ret = lan78xx_write_reg(dev, RFE_CTL, pdata->rfe_ctl);
- /* Enable or disable checksum offload engines */
- lan78xx_set_features(dev->net, dev->net->features);
-
- lan78xx_set_multicast(dev->net);
+ lan78xx_set_rx_mode(dev->net);
/* reset PHY */
ret = lan78xx_read_reg(dev, PMT_CTL, &buf);
@@ -3613,7 +3630,7 @@ static const struct net_device_ops lan78xx_netdev_ops = {
.ndo_set_mac_address = lan78xx_set_mac_addr,
.ndo_validate_addr = eth_validate_addr,
.ndo_do_ioctl = phy_do_ioctl_running,
- .ndo_set_rx_mode = lan78xx_set_multicast,
+ .ndo_set_rx_mode = lan78xx_set_rx_mode,
.ndo_set_features = lan78xx_set_features,
.ndo_vlan_rx_add_vid = lan78xx_vlan_rx_add_vid,
.ndo_vlan_rx_kill_vid = lan78xx_vlan_rx_kill_vid,
base-commit: 4e0396c59559264442963b349ab71f66e471f84d
--
2.29.2
Impressum/Imprint: https://www.ipetronik.com/impressum
